use this one:
page.makeValueBinding(surfaceElements.knob1.mSurfaceValue, hostSelectedTrackChannel.mPreFilter.mGain).setValueTakeOverModePickup().mOnValueChange = function(activeDevice, activeMapping, value, diffValue) {
it is directly on the hw control and only called by touching the encoder. It includes the diff to the last call.
I use it in the CC121 script to detect left and right turns of the encoders to trigger zoom in and out.
I got this from @Jochen_Trappe in your thread: Midi Remote - Scripting Questions